/*
 * Copyright (c) 2015, 2022, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * The Universal Permissive License (UPL), Version 1.0
 *
 * Subject to the condition set forth below, permission is hereby granted to any
 * person obtaining a copy of this software, associated documentation and/or
 * data (collectively the "Software"), free of charge and under any and all
 * copyright rights in the Software, and any and all patent rights owned or
 * freely licensable by each licensor hereunder covering either (i) the
 * unmodified Software as contributed to or provided by such licensor, or (ii)
 * the Larger Works (as defined below), to deal in both
 *
 * (a) the Software, and
 *
 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
 * one is included with the Software each a "Larger Work" to which the Software
 * is contributed by such licensors),
 *
 * without restriction, including without limitation the rights to copy, create
 * derivative works of, display, perform, and distribute the Software and make,
 * use, sell, offer for sale, import, export, have made, and have sold the
 * Software and the Larger Work(s), and to sublicense the foregoing rights on
 * either these or other terms.
 *
 * This license is subject to the following condition:
 *
 * The above copyright notice and either this complete permission notice or at a
 * minimum a reference to the UPL must be included in all copies or substantial
 * portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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package com.oracle.truffle.api.debug.impl;

import java.lang.reflect.Method;

import com.oracle.truffle.api.debug.Debugger;
import com.oracle.truffle.api.instrumentation.TruffleInstrument;
import com.oracle.truffle.api.instrumentation.TruffleInstrument.Registration;

/**
 * Instrument for registered for the debugger. Do not use directly.
 *
 * @since 0.17
 */
@Registration(name = "Debugger", id = DebuggerInstrument.ID, services = Debugger.class)
public final class DebuggerInstrument extends TruffleInstrument {

    static final String ID = "debugger";
    private static DebuggerFactory factory = getDefaultFactory();

    @SuppressWarnings("unchecked")
    private static DebuggerFactory getDefaultFactory() {
        try {
            Method createFactory = Debugger.class.getDeclaredMethod("createFactory");
            createFactory.setAccessible(true);
            return (DebuggerFactory) createFactory.invoke(null);
        } catch (Exception ex) {
            throw new AssertionError(ex);
        }
    }

    /**
     * @since 0.17
     */
    public DebuggerInstrument() {
    }

    @Override
    protected void onCreate(Env env) {
        env.registerService(factory.create(env));
    }

    /**
     * @since 0.27
     */
    public static void setFactory(DebuggerFactory factory) {
        if (factory == null || !factory.getClass().getName().startsWith("com.oracle.truffle.api.debug")) {
            throw new IllegalArgumentException("Wrong factory: " + factory);
        }
        DebuggerInstrument.factory = factory;
    }

    /**
     * @since 0.17
     */
    public interface DebuggerFactory {
        /**
         * @since 0.17
         */
        Debugger create(Env env);
    }

}
